1. Field of the Invention
The present invention relates to a multimedia browser and more particularly, to a multi-level position designating method for browsing, editing and indexing a multimedia stream.
2. Description of the Related Art
Generally, a user can obtain information while viewing a multimedia stream as it is played. However, because a multimedia stream is a series of continuous frame units, if a user wishes to view a certain portion of a multimedia stream, the user must designate the starting and ending positions of a range of interest in the multimedia stream. Thus, a user interface which allows a user to designate a certain position or range of a multimedia stream is necessary for a user to browse, edit or index a multimedia stream.
Particularly, a multimedia stream such as a motion movie, drama, or sports has a running time of at least several tens of minutes. Thus, if a user wishes to skip to a certain position or view a certain range of a multimedia stream, an interface for designating a position or range designating of a multimedia stream is necessary. Also, to generate data such as meta-data and to index information such as casting for a multimedia stream, an interface for designating a position/range of a multimedia stream would be necessary.
Accordingly, position/range designating methods have been proposed in the related art, in which a user can select a position or range on a multimedia stream by designating a starting and ending positions using a time axis. FIG. 1 shows an example of a position/range designating user interface for a multimedia stream in the related art.
Referring to FIG. 1, an entire multimedia stream A˜B is linearly displayed using a scroll bar or slider control, and a range E˜F with a starting and ending positions can be designated through an input device. When a range is designated, the user interface displays the starting frame and the ending frame of the range E˜F such that a user can determine if the correct range has been selected. As shown, the entire multimedia stream A˜B is represented by a one-level display and using the one-level display, the range E˜F must be designated.
However, in the above user interface, an entire multimedia stream is displayed by an identical one-level screen as shown in FIG. 1, regardless of the length of the multimedia stream. Therefore, a user would have more difficulty in making a minute or fine selection in a multimedia stream with a longer running time than a multimedia stream with a shorter running time.
For example, assume multimedia stream X has a length of 100 frames and multimedia stream Y has a length of 50 frames. Both multimedia streams X and Y would be represented by a scroll bar or slider control of a constant length A˜B, even though the multimedia stream X has a length twice the length of the multimedia stream Y. Accordingly, assuming that the minimum selection range of the multimedia stream Y is 2 frames, the minimum selection range of the multimedia stream X would be 4 frames. Similarly, the minimum selection range of a multimedia stream having a length of 1000 frames would be 40 frames. Therefore, in such case, a user cannot designate and view a range smaller than 40 frames.
In other words, the greater the length of a multimedia stream, the greater the difficulty to make a fine designation of the multimedia stream. As a result, a user must scroll or slide forwards and backwards along the entire multimedia stream A˜B in frame units of the minimum range to find a desired position of the multimedia stream. However, the greater the number of scrolling, the greater the period necessary for a user to find a desired position. Particularly, a substantial period of time would be necessary if a moving picture encoding method such as MPEG is used to implement the user interface. Thus, reducing the number of scrolling would improve the efficiently of the position/range designating user interface.
As discussed above, a position/range designating method in the related art allows a user to select a position or a range by a designation of the starting and ending positions of a desired range. Here, the designation can be made using an input device such as a mouse or a keyboard and using an interface such as a scroll bar or a slider control. Also, a scroll bar or slider control of a constant length is used to represent all multimedia stream, making it difficult for a user to make a fine adjustment in selecting a desired position or range.
Alternatively, a starting position and ending position of a multimedia stream can directly be input by a user. However, because the user must know the exact or absolute value, i.e. the frame number, of the position to be designated, it is more difficult for general users to use the direct input method.